> You cannot simply make a claim that (model + harness) X is better than Y, but then have no discernible difference in the output.

You definitely can in principle; that’s the entire point of the comment you are responding to. If one tool completes it in 10 minutes with little hand holding, and the other does it in one hour at 4× the cost and while needing a lot of steering, the former is arguably better even if the end result is the same.

Whether that’s specifically true and demonstrable of GPT and Claude is another question, but your blanket statement doesn’t hold as a general rule.

Claude and Codex are tools. You can't tell the difference in the output between something that was done with a ratcheting wrench vs a standard combination wrench, but your mechanic certainly knows the ratcheting wrench is better (for most tasks).

I've not used Codex to compare against, so I'm not claiming X is better than Y, but comparing tools simply on their output is naive.

" You cannot simply make a claim that (model + harness) X is better than Y, but then have no discernible difference in the output"

Sorry I think this misses the mark.

Because it's not the output but the process.

And sometimes the outcomes are not always discernable.

Codex and Claude are very different.

I use them for different things.

Their behaviour difference is obvious.

Of course it'd impossible for anyone to tell by looking at my code base 'how it was written'.

> A colleague was convinced Claude is better

That’s actually what my comment was based on; raw code output isn’t the only measure of quality. Engineers write better code if they have the tools they prefer.